The most likely cause of dead or dying animals at or near the scene of a known or suspected terrorist incident is:

• A. Chemical release
• B. Biological agent exposure
• C. Radiation exposure
• D. Fire

Answer: (A)

Dead or dying animals at a scene tied to a known or suspected terrorist incident strongly points to a chemical release. Many toxic chemicals act quickly on animals, especially through inhalation, leading to rapid distress and death. Because animals often react to airborne contaminants sooner than humans, their bodies can serve as an early warning that the atmosphere is contaminated. This makes chemical exposure the most likely cause in this scenario.

Biological agents can cause sickness or death, but they often have incubation periods and may not produce immediate deaths right at the scene, making them a less likely direct cause of dead animals observed immediately at the location. Radiation exposure could cause harm, but visible signs in animals and the presence of dead wildlife are not as immediate or reliable a cue as a rapidly acting chemical release. Fire could cause fatalities, but the specific clue of dead animals is more strongly associated with toxic chemical exposure than with fire alone.